1. Field of the Invention
The present invention relates to apparatus for ejecting molded parts from a mold, and more particularly to a molded part ejection apparatus adapted for use with a mold in an injection molding machine, in which a mold-carrying platen includes a first part ejector for axially ejecting a part, and a second part ejector for rotationally removing a core member from a molded article.
2. Description of the Related Art
In the art of injection molding articles from plastics materials, frequently the molded article will adhere to the surface of the mold, which requires either manual part removal or a power operated removal device for separating the part from the mold surface in order for the next molding cycle to proceed. Oftentimes, ejector pins are provided within one part of a two or greater part mold, the ejector pins extending through the wall of the mold to the inner surface thereof and having inner ends conforming with the adjacent interior surface of the mold. After a molded part has solidified and has cooled to a sufficient temperature that it retains its shape and the molds have been separated, the ejector pins are moved along their axes in the direction of the part to push against the part and provide a separation force for separating the part from the mold surface.
When a molded part has internal threads that are formed by an externally threaded core over which the molded material is caused to flow, removal of the part requires that the cores be unthreaded from the molded article. In that case, a rotary motor is provided to rotate the core in an unscrewing direction to separate and withdraw the core from the threaded bore.
In the past, rotary or linear actuators were separately attached to and detached from a mold or from a mold-carrying platen, depending upon whether the part could be removed by ejector pins or whether it could only be removed by unscrewing. As a result, it was often necessary to remove one type of ejector and to install the other when the type of mold was changed.
It is an object of the present invention to avoid the need to disassemble and remove one type of mold ejector and to separately install the other type.